All language subtitles for S23E12 - Racing Leathers; Evaporative Cooling Towers; Wood Rocking Chairs; Wire Wheels (1080p AMZN WEB-DL x265 Garshasp)_track4_[eng]

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Narrator:
With no car frame around them,

Motorcycle racers look
To their clothes for protection.

One-piece suits called
Racing leathers provide it.

They're made of padded leather,

And the design is form-fitting
And aerodynamic.

Motorcycle racing leathers
Are a kind of body armor.

Equipped with padding
And airbags,

The suit is a protective shell.

It must fit the rider
Like a second skin.

To achieve this, racing leathers

Are usually custom made
By a team of specialists.

They take over 40 measurements

As the racer
Assumes different poses.

The pattern maker

Types the measurements
Into a computer.

Special software creates
A pattern for the suit.

She assembles the pattern parts
On the screen

To ensure they match up

And then sends the drawings
To a printer.

It prints
The life-sized patterns

Onto large sheets
Of thin tracing paper.

A member of the team then sprays

The backs of the paper patterns
With adhesive.

She presses the patterns
Onto sheets of cardboard.

She cuts out the cardboard

Following the designs
On the paper.

The cardboard backing

Gives the patterns
A more substantial structure.

Before cutting the leather,

They clamp a sample
In an automated tool

That moves it repeatedly
Across a piece of sandpaper.

This confirms that
The leather is strong enough

To withstand
Significant abrasion.

They apply graphics
To the patterns

To estimate the placement,

And then they're ready to cut.

The cutter carves into the white
Leather with a thin blade.

He follows the lines
Of the pattern

And leaves a generous margin.

The parts will be cut
More precisely later.

He transfers the leather panels
To a large sheet of paper

Stretched across the bed
Of a printing machine.

Light glue applied to the paper

Keeps the leather pieces
In place during printing.

The printer's jets
Spray designs onto the parts.

It uses inks

That have been specially
Formulated for leather.

The inks
Start to dry immediately,

But they leave the printed
Leather to set overnight

For a full cure.

Next,
Using a hinged scissor frame,

They stretch and expand
An elastic fabric.

A member of the team
Sprays adhesive

Onto the back
Of a leather panel.

She presses a piece of kevlar
Onto the leather,

And this reinforces it.

She then places
The kevlar and leather panel

On the fabric

That's still pulled tight
In the scissor frame.

She stitches
The leather and kevlar part

To the stretched material,
Creating a ribbed pattern.

She now cuts the panel
To its final dimensions.

The elastic fabric contracts,

Causing the leather to pucker
Into accordion-like folds.

A seamstress
Stitches the ribbed panel

To the back
Of the motorcycle racing suit.

It takes over 200 parts

To achieve
The desired shape and fit.

Some of them,
Like these shoulder protectors,

Are made of molded plastic
And foam.

They're designed to dissipate
The force of an impact.

Meanwhile, at a test station,

They slam weights
Into a molded knee pad

And measure the energy
That penetrates.

Now a member of the team

Inserts a pair of pads
Into suit leg pockets

And secures them with velcro.

The suit is ready for airbags.

She installs them
Over the shoulders.

She tucks the microprocessor

And gas inflation canisters
In the hump.

This is an aerodynamic part
At the back of the suit.

She connects the sensors
And powers up the airbags.

L.E.D. Lights on the sleeve
Illuminate,

Indicating
That they're operational.

With the leather suit complete,
They sew a microfiber liner.

The liner wicks sweat
Away from the body,

Making the suit cooler to wear.

The racer suits up
And tests the fit,

And they make
Any final alterations.

These racing leathers
Are now ready

For the thrills and spills
Of the sport.

Narrator:
Evaporative cooling towers

Keep large buildings
And industrial machines cool.

Circulating liquid

Carries the excess heat
To the cooling tower,

Typically installed on the roof.

The tower uses cold water
To cool that fluid,

Then transfers the heat
To the atmosphere

Through an evaporation process.

Pumps move the fluid
Carrying the excess heat

Through the cooling tower's
Closed-circuit coil.

Nozzles spray the coil
With cold water.

The spray water
Absorbs the heat,

And the cooled fluid
Returns to the building.

Fans blow air
Onto the now warm spray water

To evaporate just enough
To release the heat.

Then the cooled water
Loops back to the spray system,

And the cycle repeats.

Depending on the size,

The coil is made up
Of as many as 56 circuits.

A circuit is a zigzagged tube
One inch in diameter.

The mill forms a continuous
Straight tube

From a strip of carbon steel.

The rollers progressively curve
The edges upward

Until they join at the top.

The last station on the mill

Welds the joined edges together
To form a continuous seam.

Next, workers
Transfer the straight tube

To a semi-automated tube bender,
Which forms it into a circuit.

Depending on the size
Of the circuit,

There can be as few as 6 bends
Or as many as 18.

To make a circuit with 18 bends

Can require a straight tube
That's over 300 feet long.

Once all the circuits are ready,
Workers stack them on a frame,

Then weld the tube ends

To the corresponding holes
Of a steel plate.

They close up the plate
With a cover called a header.

After clamping the header
In position,

They weld it in place,
Forming a pressure-tight seal.

The coil
Is now fully constructed

And ready for testing.

Technicians
Submerge it in water,

Then pump air through
At high pressure

And look for bubbles,

Which would indicate
A leak in a circuit.

If they do find a leak,

They either repair
Or replace the circuit.

Meanwhile, work is under way

On the cooling tower's
Mechanical section.

A computer-guided laser cutter
Prepares the steel panels

That make up the section's
Rugged structure.

Workers then bend the panels
Where required

With a machine
Called a press brake.

Then, they assemble the panels
To build the structure.

Meanwhile,
Another team has assembled

The mechanical section's
Ceiling,

Which houses the fans.

Workers lower this
Onto the structure.

Inside the mechanical section,
They install the belt

That links the motor's pulley
To each fan pulley.

After tightening the belt screw
With an impact wrench,

They test the fans.

Meanwhile, the coil
Has been dipped in molten zinc

To make it corrosion-resistant.

Workers mount it

Next to the cooling tower's
Mechanical section.

They cover it
With a steel housing

And install the
Water-spray system on top of it.

The sprayed cold water
Absorbs the heat

From the fluid circulating
Through the coil.

The fans then cool the water
By evaporation

As it flows downward
Through a bundle of pvc sheets.

The machine first heats the pvc
To soften it,

Then stamps it
With the mold plate.

This imprints
A proprietary pattern

Of peaks and valleys.

This pattern is the secret

To the evaporative
Cooling process

Because it moves the air
And spreads the water

In a way
That maximizes efficiency.

Workers stack the sheets
On pole supports

To construct a bundle
Of 300 sheets.

After placing the bundle
In a housing,

They install it over a basin.

This basin
Collects the cooled water

Before it's pumped back up
To the sprayers

To repeat the cycle.

This completes the cooling
Tower's lower module.

They now mate it
With the upper module,

Containing the fans,
Coil, and spray system.

This evaporative cooling tower

Has more than 300 times
The capacity

Of a typical residential
Air-conditioning system.

Now, that'spretty cool.

Narrator:
The rocking chair was invented

Back in the 18th century,

When when people first thought
Of putting skates, or rockers,

On the bottom of chairs.

The tilting movement it produces

Reminds us of a cradle
Or a rocking horse,

Which might be what makes
Rocking chairs so comforting.

These stained jumbo rockers are
Caned in a herringbone pattern

With indonesian rattan vine.

22 pieces
Of solid appalachian red oak

Form the frame and the base
Of these rocking chairs.

To start,

The carpenter connects the tenon
Joints of the stretchers

To the mortises
Of the back frame

And hammers them in place
With a rubber mallet.

A caner drains a coil
Of binder cane,

Which is soaked overnight
To make it more pliable

While weaving the back and seat
Of the rocking chair.

She uncoils
The rattan vine threads

And starts wrapping
The back frame

From bottom to top.

The wrapping and weaving process
For each chair

Lasts about eight hours

And requires about 2,000 feet
Of rattan vine threads.

When the caner reaches the end
Of a rattan vine,

She fastens a new coil
To the first one.

She staples the threads together

And closes them tight with
A pair of needle-nose pliers.

She continues wrapping
The back frame.

She tightens the wrapping
Around the frame,

Leaving no gap
Between the cane strands.

She then tucks the final strand
Underneath one of the rails.

She now starts
The weaving process

Moving from left to right,

Using the wrapping
As a base grid for the pattern.

Each thread passes over three,
Then goes under three.

She turns the frame over

To weave the back of the frame
In the same fashion.

The challenge is to keep
The weaving straight and sleek

To give it the classic
Herringbone finish.

A carpenter attaches side
Stretchers to the front posts,

Which are already assembled
To the front rounds.

He hammers the pieces in
With a rubber mallet

And assembles the seat frame
With the back posts.

There's no need for glue.

The seat caning will solidify
The rocker's structure.

A caner uses the same rattan
Vine that was used on the back

To wrap the seat frame.

He makes sure there are no gaps
Between the strands of cane

Before he starts weaving
The herringbone pattern.

He weaves
The over-under pattern

In the center of the seat,

Where there's more slack
In the wrapping.

Then he pushes the threads up
With a wooden wedge

To tighten the caning
As much as possible.

Straps reinforce
The structure of the chair

Before the seat frame is caned.

To ensure authenticity,

A carpenter brands
The left armrest of each chair

With the original branding iron
Used by the company since 1875.

He hammers the armrest
Into the back post.

Then he aligns the spokes
Of the front post

With the hole in the armrest.

A clamp keeps the back
And front post aligned

While he inserts the armrest.

A wooden wedge in the spoke
Prevents the armrest

From disconnecting
From the front post over time.

The carpenter hammers it in
With a steel hammer.

The wedge
Replaces the need for glue

And ensures a snug fit between
The armrest and the front post.

The carpenter secures
The armrest to the chair

By drilling
A solid brass carriage bolt

Through the back post.

With a belt sander,

He levels the wedge
And front post with the armrest

And makes it smooth
To the touch.

Before the runners, or rockers,
Are assembled to the base,

The carpenter stains the chair.

The oil-based stain
Protects the wood

And brings out the natural grain
Of the solid oak frame.

The stain is then sealed
With two coats of clear varnish

That will endure
High humidity levels, sun,

And climate changes.

The carpenter assembles
The runner to the base

And measures the distance
To the front post.

This ensures an even rocking
Movement on every chair.

He fastens them
With brass carriage bolts.

The finished chairs
Will endure the test of time

And provide
Comfortable seating options

For both indoors and outdoors.

Narrator:
Wheels with wire spokes

Ruled the highways
Until the 1970s,

When they were replaced
By cast alloy ones.

But factories
Still make wire wheels

For the classic car market

And for drivers who want to use
Them to customize their ride.

Wire wheels
Suspend the weight of a car

With flexible metal spokes

Arranged in
A specific geometric pattern.

They start
With an aluminum alloy disc.

A factory worker clamps the disc
In a metal spinning machine.

This machine shapes metal
As if it were a piece of clay.

It spins the disc
At a high speed,

While a series of tools
Press it to a round form.

It takes 20 minutes to transform
The flat disc into a wheel rim,

Complete with a bead
For the tire.

The process
Also causes the metal

To undergo
Molecular transformation,

And it becomes stronger.

After polishing,
A worker moves the rim

Under a tool
That punches dimples in it.

The dimples
Will accommodate nuts

That will be used
To secure the spokes.

He drills into the dimples

To create holes
For attaching the spokes.

He angles the holes slightly

So that the spokes
Sit correctly.

He stamps
The wheel's design number

And other identifying
Information

Into the outer edge
Of the wheel rim.

By now, the wheel's
Steel centerpiece

Has also taken shape.

An employee turns it
For even spacing,

As a tool
Repeatedly punctures it.

This creates rows of small holes

In both the inner ring
And outer flange.

He then drills
Those holes larger

To prepare for the spokes
To be assembled to the part.

At the next station,

A worker inserts spokes
Into a press

That bends its ends with hooks.

The angle of the hook varies

Depending on the part
Of the wheel

The spoke is to be assembled to.

He adjusts
The settings on the press

To achieve the different bends.

Then it's over
To an automatic blade

That cuts the spokes to length.

This also varies.

They cut outer spokes longer
And inner ones shorter.

He now places
The ends of the spokes

In a device that rolls them
Against a cutting block.

It carves threads in the metal
In mere seconds.

With the spokes now hooked,
Cut, and threaded,

The wire wheel
Is ready for assembly.

The employee hooks
The appropriate spokes

Into the holes
In the centerpiece.

He places the aluminum rim
Around the centerpiece.

He attaches the threaded ends
Of the spokes to the rim

Using steel nuts
That fit into the tapered holes.

He screws them
Loosely into place.

He configures the spokes

In a criss-cross
Geometric pattern,

Specified by the engineers.

This pattern is designed
For strength and flexibility,

But it also gives the wheel
A visual appeal.

Once he's laced all the spokes
From the centerpiece to the rim,

He tightens the fittings.

This secures the assembly,
But it's not the final torque.

They now transfer the loosely
Assembled wire wheel to a shaft

And turn a crank to lower
The centerpiece within the rim.

This brings the spokes
Into the correct position,

And a worker tightens them
Substantially.

All 72 of them.

He does the final tweaking
By hand.

Seven hours in the making,

This wire wheel
Is now ready to roll.

With the rubber tire attached,

He secures the wheel to the car
Using a single large nut.

It's called a knockoff nut

Because you simply knock it off
To change the tire.

It's just one of the things

That makes the wire wheel
A classic choice.